1. Field of the Invention
This invention generally relates to delivery heads for containers of substances to be nebulized or sprayed, such as aerosol containers, pumping containers and the like and, more particularly, to a new and improved delivery head of the above mentioned kind.
2. Description of the Prior Art
It is known that from a so-called aerosol container or also a non-pressurized container a spray is generated by acting on the valve actuator (in the case of aerosols) or on the pump actuator in the case of containers provided with a pump) and this spray can be nebulized at the opening of the outlet passage of the delivery head when a break-up insert made of metal or plastic is placed in this opening, which has just the purpose to act as a restriction in order to cause a pressure drop and therefore a greater fluid rate, by letting the fluid flow to pass through suitable turbolence generating passages so as to nebulize it. Therefore, the fluid flows out of the break-up insert in the form of a nebulized spray in more or less small droplets and this depending on the number of the flow passages, the turbolence generating passage cross-sections and the pressure upstream the break-up insert.
Without this break-up insert, the nebulization can be obtained, in the case of aerosol containers, by increasing the inner pressure of the container only, (which has the disadvantage of generating a very stiff spray), whereas in the case of containers provided with a pump the nebulization cannot be obtained. The technology for making such break-up inserts and their correct positioning at the opening of the outlet passage of the delivery head have reached very sophisticated levels because, as already said, the break-up insert must permit a very accurate control of the fluid flow rate.
In the case of break-up plastic inserts, their manufacturing is carried out separately from the delivery heads and, once the inserts have been produced, they are positioned at the outlet opening of the delivery heads later, by means of specific automatic machines which have to exhibit a high production rate and an extreme precision in the assembly step.